Leakages in High pressure Urea grade nozzles, lens gaskets.

[EngTal]

How to handle a situation in which there is a Urea-Carbamate leakage through a High-pressure Urea grade nozzle and lens gasket.
What to do if the tightening margin is finished after hot tightening?
What should we take care of during installation to avoid such leakages after plant startup?

 

[A8yssUK]

Also... just to make sure.... you did use a brand new gasket right ?

 

[LittleInch]

The entire drip ring thing IS the "gasket".... As far as I can figure out.

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[A8yssUK]

@littleinch

Yeah, that's right, it's basically two gaskets and a separator but forged together

 

[XL83NL]

There's just so much going here, that Im puzzled by each of the OP's reply and how it seems he thinks he can may away with a quick fix, rather than understanding the real (safety) issue here.

Huub
- You never get what you expect, you only get what you inspect.

 

[A8yssUK]

@XL83NL
Your right the fact they mentioned a "spanner" and "striking" it worries me...if they are indeed just using a spanner and not at minimum a wrench (this might be due to translation)... perhaps the reason its leaking is they don't have enough bolt force and cannot generate it with a hand spanner... from the photo they look like what M32-M36 nuts... the lens gasket requires a lot of gasket stress as its metal-metal... this requires a lot of bolt force which requires a LOT of torque... 1000+ Nm at a rough guess... which would require a really long spanner..

 

[LittleInch]

Or a very big hammer...

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.

 

[r6155]

I insist with hydraulic tensioner for studs, NEVER TORQUE !!.
The extra length of bolts (see photo) is for installing the hydraulic tensioner.
Regards

 

[XL83NL]

@A8yssUK: there's just too much not to mention.
[ul]
[li]no lubricant,[/li]
[li]no details on the flanged joint,[/li]
[li]no mention of an assembly procedure or anything written down in there (which I would presume to be present for such (1000 Nm +?) studs, [/li]
[li]a lens ring (is it a ring joint, or ...?), [/li]
[li]a striking spanner, [/li]
[li]studs not equally aligned (or eccentrically aligned on purpose for ease of disassembly)), [/li]
[li]studs that use B1.20.1 pipe threads, [/li]
[li] etc..[/li]
[/ul]
What could be an issue here is the language barrier for the OP. I suspect this is somewhere in Italy, I know from experience their English isn't all that.

Huub
- You never get what you expect, you only get what you inspect.

 

[Heaviside1925]

OP,
I agree with tug, I think your drip leg is your issue. Since the lens gaskets seal based on deformation, consider the difference between the left and right sides.

It appears the drip leg (right side) is much less compressed than the left, indicating it is the drip leg preventing further compression/deformation to provide the required seal. Consider compression in the direction of the drip leg as shown below and what is resisting further compression.

 

[LittleInch]

Only one side has this drip leg. The LHS just ahs a slim line lens gasket.

But yes, the fact the hardenss of the gasket is specifically noted as max 160 BH, indicates it is designed to deform.

So a use once only gasket seal.

This is quite good, especially slides 42 to 50 on lens type gasket.

https://ureaknowhow.com/wp-content/uploads/2018/03/hand_out_urea_clinic_2018_part2.pdf

Remember - More details = better answers
Also: If you get a response it's polite to respond to it.